danvers



UNITED STATES PATENT OFFICE.

P. DANVERS, OF NEW YORK, N. Y.

STEAM-HAMMER.

Specification of Letters Patent No. 21,489, dated September 14, 1858.

To all whom fit may concern:

Be it known that I, PATRICK DANVERS, of the city, county, and State of New York, have invented a new and useulImprovement in Steam-Hammers; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawing, forming part of this specification, said draw ing representing a central vertical section of a steam-hammer constructed according to my invention.

My improvement consists in the employ ment, in combination with that kind of steamwhaminer whose hammer block or ram consists of or forms part or" a cylinder or ram working on a stationary piston, of an external stationary cylinder which receives a piston on the head of the reciprocating cylinder or ram and which is furnished with a proper system or' valves to admit steam to act above the last-named piston for the purpose of adding the force due to the pressure of steam on the said pistn to the force due to the tall of the ram by gravita tion and thereby increasing the power of the hammer besides making its operation quicker.

To enable others skilled in the art to make and use. my invention, I will proceed to describe its construction and operation.

1, in the drawing, represents the framing which is of a form substantially like that generally heretofore adopted for steam hammers.

2, is the external cylinder which const-i tutes the principal feature of my invention, occupying the position generally occupied by the guides, and either cast with or securely bolted to the framing. This cylinder is open at the bottom, but closed at the top by a head 10, which constitutes the bottom of the steam chest 1l.

3, is the reciprocating cylinder or ram, having at its head the piston Ll, which is iitted steam tight to the cylinder 2, and properly packed.

5 is the stationary piston attached by a tubular rod 6, to the head l0, of the external cylinder and iitted steam tight to the interior of the reciprocating cylinder or ram. The head of the latter cylinder or ram is fitted with a stuffing-box or otherwise properly packed steam-tight around the rod 6.

7 is the anvil.

Steam is admitted to the cylinder or ram 3, above the piston 5, by a valve S, on the steam chest 11, which valve is opened at the proper time by hand or by suitable mechanism to allow the steam to pass through the hollow piston rod. The steam thus admitted raises the said cylinder or ram. Another valve (not shown) is provided for the eX- haust of the steam from said cylinder when it has been raised to the proper height and it is required to descend to strike the blow. A valve 9, similar to 8, is represented for the admission of steam to the upper part of the external cylinder to act above the piston f1, to increase the force of the descent of the cylinder or ram 3, and the blow of the hammer. By connecting these valves by a lever l2, one valve is opened by the act of closing the other, and the action of the steam on one is made to balance its action on the other. An exhaust valve (not shown) is also provided for the cylinder 2, and this may be connected with the exhaust valve of the cylinder 3, in the same manner as the steam valves are connected.

I do not consider it necessary to describe particularly the valves or valve gear, as almost any system of valves and gear suitable for steam engines may be applied, as will be well understood by engineers.

I do not claim the combination of t-he reciprocating cylinder and stationary piston, as that constitutes what is known as the Condie steam hammer. Nor do I claim attaching the hamm er to a piston working in a stationary cylinder, as that constitutes Nasmyths steam hammer. But

That I claim as my invention, and desire to secure by Letters-Patent, is

The combination .with the reciprocating cylinder or ram 3, which constitutes or has attached to it the hammer-block, and the stationary piston 5, of the piston 4 and the external steam cylinder 2, provided with a proper system of valves; the whole operating substantially as herein specified.

P. DANVERS.

In presence (if- JAMES F. CHAMBERLMN, JOHN GLAss. 

